If there is black, red or dark colors I would probably test a small piece. I put into very hot water then lay out on a white paper towel to see if the fabric will bleed. I learned to do this after I had a quilt top all quilted then wet it to block it, The red bled terribly and ruined the quilt. I washed what was left about 10 times and it was still bleeding. Made a dog bed for my son from it, so it can eventually be thrown away.